1. Field of the Invention
The present invention relates to a gas generator which includes a housing filled with a gas generating charge for generating a combustion gas and a squib for igniting the gas generating charge.
2. Description of Related Art
JP 2004-217059 A discloses a conventional gas generator which includes a tubular housing body that houses a gas generating charge, a squib for igniting the gas generating charge and a holder section that holds the squib. The holder section includes a holder body made from metal and a molded section which is located between the holder body and the squib and made from synthetic resin. The holder body includes an outer cylinder section that covers an outer circumference of the molded section and a protruding section that protrudes inwardly from an end region of the outer cylinder section on the side of the gas generating charge and is formed along an entire circumferential direction of the outer cylinder section continuously. The molded section includes a generally tubular cover section that covers conductive pins of the squib which protrude from the protruding section in an interior of the outer cylinder section, and a set-in portion that is located on the side of the gas generating charge relative to the protruding section and covers an outer circumference of an igniter of the squib in a closely contacting fashion. The protruding section is covered by the molded section all over.
That is, in the conventional gas generator, the protruding section of the holder body has an outer contour like a generally doughnut disc, and the molded section located between the holder body and the squib has such an outer contour that is constricted partially according to the contour of the protruding section. Further, the protruding section has a generally uniform thickness in a sectional contour as taken along an axial direction of the housing body as referred to FIG. 2 of the above prior art reference. Such contours of the protruding section and molded section form narrow regions in a cavity of a mold used to mold the molded section, e.g., between the igniter and protruding section, between an opening formed on the protruding section and the conductive pins of the squib, etc. At molding of the molded section, a molten synthetic resin is fed into a mold from a gate formed at either one end face in an axial direction of the housing body to flow through the narrow regions of the cavity. The narrow regions are likely to cause problems in resin flow and resultant defective moldings.